Visible by satellite, the loop current is the rush of hot Caribbean water that pushes into the Gulf between Cuba and Mexico. It bends toward the southwest coast and then whirls around east, forming a hairpin turn before swooping back out into the Atlantic via the Florida straits.

Helene’s storm clouds are expected to become better organized with a more defined rotation as it enters a favorable environment.

The forecast refers to the potential for rapid intensification over the Gulf of Mexico, which is when a storm gains 35 mph or more in a 24-hour period.